The quality of input power feeding the electronics intrigues me, and always looking for ways to improve that part of the audio chain (and frankly, to bling up the system). I was away in HongKong/Singapore recently, and along the way I purchased a EMF/RF meter (TM-190):

This to me is an incredible useful tool as it allows me to check:

shielding of power cables

if my audio equipment is grounded properly

general noise interference

This TM-190 replaces the Deta voltage tester. So instead of a binary measurement (beep vs no beep), the TM-190 now gives me proper readings so I can make better subjective correlations between interference vs sound quality (and perhaps find out if there are any ghosts!).

So the first thing to test is naturally is the GPO (switched dedicated 15A dual outlets). This is the measurement with switch in the OFF position:

The measurement is 577 V/m. OK that sets the baseline, so let's see what happens if we turn both outlets to the ON position:

Now it reads 1063 V/m, nearly 2x the reading! What does this mean? To be honest, I don't have a clue, and if I'm to guess - probably nothing!

But bling up the GPO try I must, and here's the new GPO which I hope will be an easy fit. Introducing, the SW-2XT(L) US from SineWorld:

And here's the outlet out of the box (pun?):

That is one thick metal block (platinum over bronze):

The metal faceplate is actually earthed. That has to be a good thing (I hope):

Notice how the live and neutral has 4 holes, and only one earth? There are potential benefits of improvement by using different cabling strategies here. But I'm not going to explore them as I only have one dedicated power cable in the wall.

Hopefully I can take some measurements when the GPO's fitted. Watch this space.

It is so much easier now to plug/unplug cables into the wall GPO now, as the GPO socket grabs and holds the power cables firmly. Notice how the orientation is such that the plugs are plugged sideways (i.e. Earth is on the right rather than at the top)? This orientation makes sense after I plugged in the power cable, the flat live and neutral pins of the power cables are horizontal and is able to hold the cable up. Absolutely the attention to detail here.

Being unswitched outlets I always fear there will be sparks as I plug/unplug the power cables. Surprisingly that didn't happen .

So here are some quick (and unexpected) measurements. This is the EMF reading of the SineWorld GPO without any connections:

Gah I hate a non flat wall!

Back on topic it's now a lower Electrical Field (EF) reading, that's only approximately 31% of the original reading! Slightly higher magnetic field (MF) though, I'm guessing that big bronze faceplate with platinum plating is the cause of this extra MF.

And what with power cables plugged in?

That's only an increase of 48 V/m when compared to the bare SineWorld GPO. More importantly, this reading is a marked 15% of the original switched GPO. Higher MF reading though (again I suspect it the big metal plate to be the culprit).

So what does all this mean? On the surface this seems to be a zero sum game, a lower EF is cancelled out by a higher MF.

And do these EMF mattter really? Unlike RF, when using the these units of measurements, EMF don't have a lot of "transmitting" power, this is the reason why the meter is placed so close to the outlet - the further you are from the source the weaker the field (logarithmic power loss).

If you are in a big listening room, the GPO will not be able to influence most equipment due to distance. The power cable is the only exception as it's right next to the source! The ground may have some induced noise and that may result in a small fluctuation. However most people would never consider a power cable an audio equipment so this GPO mod is moot.

For me this reinforces a potential benefit of using after market power cables that are shielded. That will help in the EF side of things.

Would this mod translate to better SQ? To evaluate this aspect I have to wait a few weeks to find out.

As a final note, the usual disclaimer applies. If you reside in Australia do not ever fit this power outlet! No sparky will ever install this for you and the cons far outweighs any pros, especially if you DIY!